Precisely tailoring metal single-atoms within zeolite scaffolds and understanding the origin of the unique behavior of such atomically dispersed catalysts are pivotal and challenge in chemistry and catalysis.Herein,we...Precisely tailoring metal single-atoms within zeolite scaffolds and understanding the origin of the unique behavior of such atomically dispersed catalysts are pivotal and challenge in chemistry and catalysis.Herein,we have successfully fabricated Ni single-atoms within BEA zeolite(Ni_(1)@Beta)through a facile in situ two-step hydrothermal strategy,notably without using any chelating agent for stabilizing Ni species.With the aid of advanced characterization techniques,such as aberration-corrected high-angle annular dark-field scanning transmission electron microscopy,X-ray absorption spectroscopy,etc.,and combined with density functional theory calculations,the nature and micro-environment of isolated Ni species,which are incorporated within 6-membered rings and stabilized by four skeletal oxygens of Beta zeolite,have been identified.The as-obtained Ni1@Beta exhibits a superior performance in terms of activity(with a turnover frequency value up to 114.1 h^(-1))and stability(for 5 consecutive runs)in the selective hydrogenation of furfural,surpassing those of Ni nanoparticle analogues and previously reported Ni-based heterogeneous catalysts.This study provides an efficient strategy for the fabrication of non-noble metal single-atoms within zeolites,which could be of great help for the design of metal-zeolite combinations in the chemoselective reactions involved in biomass conversion and beyond.展开更多
Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulatio...Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge.Herein,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation.Compared with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.展开更多
With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. D...With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.展开更多
Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as ...Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as inactive sites,dissolution,and oxidation,amongst others.Herein,we applied a model catalyst s-Ni(OH)2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap.The advanced operando synchrotron radiation Fourier transform infrared(SR-FTIR)spectroscopy,synchrotron radiation photoelectron spectroscopy(SRPES)depth detection and differential X-ray absorption fine structure(D-XAFS)spectrum jointly point out that some oxidized sulfur species(SO_(4)^(2-))will selfoptimize new Ni–S bonds during OER process.Such amazing anionic self-optimization(ASO)behavior has never been observed in the OER process.Subsequently,the optimization-derived component shows a significantly improved electrocatalytic performance(activity,stability,etc.)compared to reference catalyst Ni(OH)_(2).Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst,and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER,respectively.This work demonstrates the vital role of anions in the electrochemical process,which will open up new perspectives for understanding OER and provide some new ideas in related fields(especially catalysis and chemistry).展开更多
Purpose A new mobile grazing-incidence X-ray absorption fine spectroscopy(GIXAFS)endstation was developed at Beijing Synchrotron Radiation Facility(BSRF)to improve the function of general XAFS beamlines and extend the...Purpose A new mobile grazing-incidence X-ray absorption fine spectroscopy(GIXAFS)endstation was developed at Beijing Synchrotron Radiation Facility(BSRF)to improve the function of general XAFS beamlines and extend their capabilities to a wider user community.Methods We developed a facile GIXAFS endstation through modifying the regular XAFS in grazing-incidence geometry.Additionally,a soller slit,filter,photographic film and tiny lead sheets were assembled to improve the signal-to-noise ratio of XAFS data.Furtherly,combined with time-resolved quick scanning XAFS(QXAFS)techniques,the systems can perform in situ XAFS measurement to study materials under operando condition.Results The GIXAFS had been used to collect the Ga K-edge XAFS of InGaN thin film on sapphire substrate,which demonstrated that signal-to-noise ratio of XAFS data had been greatly improved through suppressing the effect of substrate diffractions.Moreover,the feasibility of GIXAFS-QXAFS combination was illustrated with in situ exploring the degradation of organic-inorganic perovskites under X-ray radiation.Conclusion A new mobile and facile GIXAFS endstation has been developed for thin films study.Based on the photographic film and lead sheets,the contamination of the XAFS from the matrix is minimized.Further combined with QXAFS techniques,the systems are used to reveal the X-ray-induced organic-inorganic perovskite thin films photodegrading process,which proved their successful application in the time-resolved measurements,extending the capabilities of general beamlines available to a wider user community.展开更多
文摘Precisely tailoring metal single-atoms within zeolite scaffolds and understanding the origin of the unique behavior of such atomically dispersed catalysts are pivotal and challenge in chemistry and catalysis.Herein,we have successfully fabricated Ni single-atoms within BEA zeolite(Ni_(1)@Beta)through a facile in situ two-step hydrothermal strategy,notably without using any chelating agent for stabilizing Ni species.With the aid of advanced characterization techniques,such as aberration-corrected high-angle annular dark-field scanning transmission electron microscopy,X-ray absorption spectroscopy,etc.,and combined with density functional theory calculations,the nature and micro-environment of isolated Ni species,which are incorporated within 6-membered rings and stabilized by four skeletal oxygens of Beta zeolite,have been identified.The as-obtained Ni1@Beta exhibits a superior performance in terms of activity(with a turnover frequency value up to 114.1 h^(-1))and stability(for 5 consecutive runs)in the selective hydrogenation of furfural,surpassing those of Ni nanoparticle analogues and previously reported Ni-based heterogeneous catalysts.This study provides an efficient strategy for the fabrication of non-noble metal single-atoms within zeolites,which could be of great help for the design of metal-zeolite combinations in the chemoselective reactions involved in biomass conversion and beyond.
基金supported by the National Natural Science Foundation of China (22288101,21991090,21991091,22078316,22272171 and 22109167)the Sino-French International Research Network (Zeolites)+2 种基金the BL01B1 beamline of SPring-8 and the 1W1B station of Beijing Synchrotron Radiation Facility (BSRF)for the support of XAS measurementsthe Division of Energy Research Resources of Dalian Institute of Chemical Physics for the support of iDPC-STEM measurementsthe support of the Alexander von Humboldt Foundation (CHN 1220532 HFST-P)。
文摘Zeolite-encapsulated metal nanoclusters are at the heart of bifunctional catalysts,which hold great potential for petrochemical conversion and the emerging sustainable biorefineries.Nevertheless,efficient encapsulation of metal nanoclusters into a high-silica zeolite Y in particular with good structural integrity still remains a significant challenge.Herein,we have constructed Ru nanoclusters(~1 nm)encapsulated inside a high-silica zeolite Y(SY)with a SiO_(2)/Al_(2)O_(3) ratio(SAR)of 10 via a cooperative strategy for direct zeolite synthesis and a consecutive impregnation for metal encapsulation.Compared with the benchmark Ru/H-USY and other analogues,the as-prepared Ru/H-SY markedly boosts the yields of pentanoic biofuels and stability in the direct hydrodeoxygenation of biomass-derived levulinate even at a mild temperature of 180℃,which are attributed to the notable stabilization of transition states by the enhanced acid accessibility and properly sized constraints of zeolite cavities owing to the good structural integrity.
基金supported by the National Basic Research Program of China (2022YFA1603701, 2021YFA1200900)the institutionalized scientific research platform relies on Beijing Synchrotron Radiation Facility of Chinese Academy of Sciences,the Strategic Priority Research Program of Chinese Academy of Sciences (XDB36000000)+2 种基金the National Natural Science Foundation of China (22027810, 82341044,22388101 and 22307028)the CAMS Innovation Fund for Medical Sciences(CIFMS 2019-I2M-5-018)the New Cornerstone Science Foundation。
文摘With the advancement of modern science and technology, large scientific facilities are increasingly oriented toward demand and application, and can be used for basic research as well as serving multiple disciplines. Developing large scientific facilities and related analytical technologies enhances understanding of large scientific facilities and popularizes their application in research across multiple disciplines. The combination of light or neutron sources from large scientific facilities and advanced analytical technologies can be achieved for materials structure information, dynamics study of chemical reactions, high dissociation of biomolecules, 3D visualization of energy materials or biological samples, etc. We first introduce the progress of domestic large scientific facilities of synchrotron radiation(SR) and free electron lasers(FELs) with different wavelengths and neutron sources.We further discuss the comparison between Chinese and typical foreign facilities in X-ray radiation from X-ray tubes, synchrotrons, X-ray FELs, and neutron sources based on physical parameters of light and neutron sources. In addition, we focus on the technological progress and perspectives combined with advanced X-ray radiation and neutron sources of large scientific facilities in China, especially in the nanoscience fields of energy catalysis and biological science. We hope that this roadmap will provide references on technology and methods to experimental users, as well as prospects for future development of technologies based on large research infrastructure facilities. Comprehensive studies and guidelines for basic research to practical application in various disciplines can be made with the assistance of large scientific facilities.
基金supported in part by the National Key R&D Program of China(2017YFA0303500)the National Natural Science Foundation of China(U1932201,21727801,and 51902303)+4 种基金the National Natural Science Foundation of China-Ministry of Foreign Affairs and International Cooperation of Italy(51861135202)CAS International Partnership Program(211134KYSB20190063)Key Research Program of Frontier Sciences(QYZDB-SSW-SLH018)the University of Science and Technology of China start-up fundCAS Interdisciplinary Innovation Team。
文摘Broadly,the oxygen evolution reaction(OER)has been deeply understood as a significant part of energy conversion and storage.Nevertheless,the anions in the OER catalysts have been neglected for various reasons such as inactive sites,dissolution,and oxidation,amongst others.Herein,we applied a model catalyst s-Ni(OH)2 to track the anionic behavior in the catalyst during the electrochemical process to fill this gap.The advanced operando synchrotron radiation Fourier transform infrared(SR-FTIR)spectroscopy,synchrotron radiation photoelectron spectroscopy(SRPES)depth detection and differential X-ray absorption fine structure(D-XAFS)spectrum jointly point out that some oxidized sulfur species(SO_(4)^(2-))will selfoptimize new Ni–S bonds during OER process.Such amazing anionic self-optimization(ASO)behavior has never been observed in the OER process.Subsequently,the optimization-derived component shows a significantly improved electrocatalytic performance(activity,stability,etc.)compared to reference catalyst Ni(OH)_(2).Theoretical calculation further suggests that the ASO process indeed derives a thermodynamically stable structure of the OER catalyst,and then gives its superb catalytic performance by optimizing the thermodynamic and kinetic processes in the OER,respectively.This work demonstrates the vital role of anions in the electrochemical process,which will open up new perspectives for understanding OER and provide some new ideas in related fields(especially catalysis and chemistry).
基金support by the National Key Research and Development Program of China(Grant No.2017YFA0403400)the National Natural Science Foundation of China(NSFC)(U1932201,U2032202)
文摘Purpose A new mobile grazing-incidence X-ray absorption fine spectroscopy(GIXAFS)endstation was developed at Beijing Synchrotron Radiation Facility(BSRF)to improve the function of general XAFS beamlines and extend their capabilities to a wider user community.Methods We developed a facile GIXAFS endstation through modifying the regular XAFS in grazing-incidence geometry.Additionally,a soller slit,filter,photographic film and tiny lead sheets were assembled to improve the signal-to-noise ratio of XAFS data.Furtherly,combined with time-resolved quick scanning XAFS(QXAFS)techniques,the systems can perform in situ XAFS measurement to study materials under operando condition.Results The GIXAFS had been used to collect the Ga K-edge XAFS of InGaN thin film on sapphire substrate,which demonstrated that signal-to-noise ratio of XAFS data had been greatly improved through suppressing the effect of substrate diffractions.Moreover,the feasibility of GIXAFS-QXAFS combination was illustrated with in situ exploring the degradation of organic-inorganic perovskites under X-ray radiation.Conclusion A new mobile and facile GIXAFS endstation has been developed for thin films study.Based on the photographic film and lead sheets,the contamination of the XAFS from the matrix is minimized.Further combined with QXAFS techniques,the systems are used to reveal the X-ray-induced organic-inorganic perovskite thin films photodegrading process,which proved their successful application in the time-resolved measurements,extending the capabilities of general beamlines available to a wider user community.
